1. Field of the Invention
The present invention relates to a device for feeding oil to a seat of a bearing that supports a rotatable shaft.
2. Description of the Prior Art
With rotatable shafts supported in oil-lubricated bearings, a continuous feeding of oil to bearing seats is insured by an oil feeding device. There exists different devices or arrangements for feeding oil, e.g., oil can be fed to bearing seats by a separately driven oil pump through tubular conduits. Also know is an arrangement with which a lower end of a rotatable vertical shaft is submerged in an oil reservoir, and a section of the shafts, which is formed as a helical thread, forms a device for feeding oil to bearing seats. For feeding oil to bearing seats from an oil reservoir, also, wicks can be used. This solution, however, does not allow to monitor the flow of oil.
In all of the above-discussed cases, a continuous and uniform feeding of oil depends on a mounting position of the rotatable shaft. In many cases it is desirable that the mounting position of a shaft is not prefixed but is variable so that the position can be adapted to a particular use. E.g., with the use of turbomolecular pumps which are equipped with rapidly rotatable rotor shafts with which a continuous and uniform feeding of oil to bearing seats is particularly important, the rotor shaft can occupy different positions dependent on a particular use of the turbomolecular pump, e.g., the rotor shaft can occupy a vertical, horizontal or overhead position.
The conventional oil feeding devices significantly limit the mounting positions the shaft can occupy. During transportation of the machines or apparatuses with oil-lubricated bearings, oil should be removed from a reservoir as a predetermined or prefixed position of the shaft cannot be maintained during transportation.
Accordingly, an object of the present invention is to provide a device for feeding oil to bearing seats of a rotatable shaft and which would insure a continuous and uniform feeding of oil and monitoring of oil flow independent on the mounting position of the rotatable shaft.
Another object of the present invention is to provide an oil-feeding device that would insure transportation of the machine and apparatuses with oil-lubricated bearings of the rotatable shafts, without removing oil from the oil reservoir.